Typical extracorporeal insulin pumps are carried by a patient night and day and are manufactured, among others, by Disetronic Medical Systems AG, Switzerland. Below, reference is mainly made to extracorporeal insulin pumps for illustrative purposes without excluding other ambulatory devices.
Insulin pumps may require a number of service operations to be performed by the user, for example, service operations for replacing disposables. While some of those disposables have a specified lifetime, the lifetime of other disposables is highly dependent on the individual application conditions and may vary in a large range. For example, a typical drug cartridge stores a maximum of 3 ml or 300 IU (International units) of insulin and may have an average lifetime of one week or even more than one week for a first patient. In another example, a typical drug cartridge storing a maximum of 3 ml or 300 IU (International units) of insulin may have an average lifetime of 3 days for a second patient. Furthermore, the lifetime of many disposables is not constant but shows a significant variability even for one and the same patient or user. Alerts are provided by insulin pumps to inform the user about upcoming service operations and may comprise an acoustic and/or tactile indication. Such alerts, however, are often felt as bothersome and inconvenient.
In order to reduce inconvenience resulting from the need for replacing disposable and carrying out further service operations, insulin pumps are available, such as the OmniPod® system from Insulet Corporation, USA, which reduce the operation to replacing the infusion pump as a whole every few days. However, those disposable pumps are critical with respect to long-term costs, as well as waste generation and wearing comfort for some users.
While a variety of convenient, cost-effective ambulatory medical devices may exist, it is believed that no one prior to the inventors has made or used the inventive examples as described herein.